philwinder
Member level 1
lc filter power supply
Hi,
Where is the best place to put a LC power supply filter?
Since when I place it before any voltage regulators {i.e. directly on the power input to the board (DC from a S.M. power supply) } I still get a lot of noise on some high gain amplifiers even when using low noise regulators (LP3878 - National). I would have thought that the regulators PSRR would have improved the noise, not made it worse.
However, placing the LC after the regulators, before the op amp power terminals, I get minuscule amounts of noise! Although, I dont want to put a big LC pair on every amp power input!
Cheers,
Phil
Hi,
Where is the best place to put a LC power supply filter?
Since when I place it before any voltage regulators {i.e. directly on the power input to the board (DC from a S.M. power supply) } I still get a lot of noise on some high gain amplifiers even when using low noise regulators (LP3878 - National). I would have thought that the regulators PSRR would have improved the noise, not made it worse.
However, placing the LC after the regulators, before the op amp power terminals, I get minuscule amounts of noise! Although, I dont want to put a big LC pair on every amp power input!
Cheers,
Phil